1/* Copyright (c) 2016, Facebook
 2 *
 3 * This program is free software; you can redistribute it and/or
 4 * modify it under the terms of version 2 of the GNU General Public
 5 * License as published by the Free Software Foundation.
 6 */
 7#include <linux/skbuff.h>
 8#include <linux/netdevice.h>
 9#include <linux/version.h>
10#include <uapi/linux/bpf.h>
11#include <uapi/linux/perf_event.h>
12#include <bpf/bpf_helpers.h>
13#include <bpf/bpf_tracing.h>
14
15struct {
16	__uint(type, BPF_MAP_TYPE_HASH);
17	__type(key, long);
18	__type(value, long);
19	__uint(max_entries, 1024);
20} my_map SEC(".maps");
21struct {
22	__uint(type, BPF_MAP_TYPE_PERCPU_HASH);
23	__uint(key_size, sizeof(long));
24	__uint(value_size, sizeof(long));
25	__uint(max_entries, 1024);
26} my_map2 SEC(".maps");
27
28struct {
29	__uint(type, BPF_MAP_TYPE_STACK_TRACE);
30	__uint(key_size, sizeof(u32));
31	__uint(value_size, PERF_MAX_STACK_DEPTH * sizeof(u64));
32	__uint(max_entries, 10000);
33} stackmap SEC(".maps");
34
35#define PROG(foo) \
36int foo(struct pt_regs *ctx) \
37{ \
38	long v = PT_REGS_IP(ctx), *val; \
39\
40	val = bpf_map_lookup_elem(&my_map, &v); \
41	bpf_map_update_elem(&my_map, &v, &v, BPF_ANY); \
42	bpf_map_update_elem(&my_map2, &v, &v, BPF_ANY); \
43	bpf_map_delete_elem(&my_map2, &v); \
44	bpf_get_stackid(ctx, &stackmap, BPF_F_REUSE_STACKID); \
45	return 0; \
46}
47
48/* add kprobes to all possible *spin* functions */
49SEC("kprobe/spin_unlock")PROG(p1)
50SEC("kprobe/spin_lock")PROG(p2)
51SEC("kprobe/mutex_spin_on_owner")PROG(p3)
52SEC("kprobe/rwsem_spin_on_owner")PROG(p4)
53SEC("kprobe/spin_unlock_irqrestore")PROG(p5)
54SEC("kprobe/_raw_spin_unlock_irqrestore")PROG(p6)
55SEC("kprobe/_raw_spin_unlock_bh")PROG(p7)
56SEC("kprobe/_raw_spin_unlock")PROG(p8)
57SEC("kprobe/_raw_spin_lock_irqsave")PROG(p9)
58SEC("kprobe/_raw_spin_trylock_bh")PROG(p10)
59SEC("kprobe/_raw_spin_lock_irq")PROG(p11)
60SEC("kprobe/_raw_spin_trylock")PROG(p12)
61SEC("kprobe/_raw_spin_lock")PROG(p13)
62SEC("kprobe/_raw_spin_lock_bh")PROG(p14)
63/* and to inner bpf helpers */
64SEC("kprobe/htab_map_update_elem")PROG(p15)
65SEC("kprobe/__htab_percpu_map_update_elem")PROG(p16)
66SEC("kprobe/htab_map_alloc")PROG(p17)
67
68char _license[] SEC("license") = "GPL";
69u32 _version SEC("version") = LINUX_VERSION_CODE;